Generally there exists a variety of different stacked assemblies and structures in the context of electronics and electronic products.
The motivation behind the integration of electronics and related products may be as diverse as the related use contexts. Relatively often size savings, weight savings, cost savings, or just efficient integration of components is sought for when the resulting solution ultimately exhibits a multilayer nature. In turn, the associated use scenarios may relate to product packages or food casings, visual design of device housings, wearable electronics, personal electronic devices, displays, detectors or sensors, vehicle interiors, antennae, labels, vehicle electronics, etc.
Electronics such as electronic components, e.g. ICs (integrated circuit), and conductors, may be generally provided onto a substrate element by a plurality of different techniques. For example, ready-made electronics such as various surface mount devices (SMD) may be mounted on a substrate surface that ultimately forms an inner or outer interface layer of a multilayer structure. Additionally, technologies falling under the term “printed electronics” may be applied to actually produce electronics directly and additively to the associated substrate. The term “printed” refers in this context to various printing techniques capable of producing electronics/electrical elements from the printed matter, including but not limited to screen printing, flexography, and inkjet printing, through substantially additive printing process. The used substrates may be flexible and printed materials organic, which is however, not necessarily always the case.
A substrate such as a plastic substrate film, may be subjected to processing like (thermo)forming and molding. Indeed, using e.g. injection molding a plastic layer may be provided on the film, potentially then embedding a number of elements such as electronic components initially provided on the film. The plastic layer may have different mechanical, optical, electrical, etc. properties. It may simply secure or protect underlying elements, provide desired feel or appearance to the product such as color. The molded plastic layer may further be covered by additional elements or e.g. a foil or film, which may contain e.g. graphical patterns obtained by IML/IMD techniques.
The obtained multilayer, or stacked, structure may be configured for a variety of purposes depending on the included features such as electronics and the intended use scenario and related use environment. Different optical, sensing, or e.g. attachment functionalities may be required. Typically such functionalities are provided by dedicated elements specifically included in the structure. Increasing the overall number of elements in the stack tends to increase the complexity, time span and cost of the associated manufacturing process, while reducing the integration level and increasing the size and weight of the overall structure.